解二次方程(因式分解法)

解二次方程(因式分解法)
几何画板及绘图内容加载中,请稍等……
2017-12-27 16:01
①本范例演示如何通过因式分解法解非标准形式的二次方程;②涉及核心数学概念:二次方程、因式分解、根的求解;③构造要点:使用了RandomElement, Random, Simplify, Coefficients, RandomPolynomial, Factor, GCD, If等GeoGebra命令与对象;④适合高中数学教学,帮助学生练习和掌握二次方程的解法。

GeoGebra 命令及参数

  1. RandomElement({-3, -2, -1, 1, 2, 3}) → a
  2. Random(-10, 10) → d
  3. Random(-10, 10) → c
  4. RandomElement({-3, -2, -1, 1, 2, 3}) → b
  5. Simplify((((a * x) - c) * ((b * x) - d))) → final
  6. Coefficients(final) → list1
  7. RandomPolynomial(2, -7, 7) → right
  8. Simplify(final(x) + right(x)) → left
  9. Factor(final) → f
  10. GCD(a, c) → gcdac
  11. GCD(b, d) → gcdbd
  12. Simplify(If[a < 0, ((a * x) - c) / ((-gcdac)), ((a * x) - c) / gcdac]) → factor1
  13. Simplify(If[b < 0, ((b * x) - d) / ((-gcdbd)), ((b * x) - d) / gcdbd]) → factor2
  14. If(c / a < 0, "-" + (FractionText[abs(c / a)]), "" + (FractionText[abs(c / a)])) → text5
  15. If(d / b < 0, "-" + (FractionText[abs(d / b)]), "" + (FractionText[abs(d / b)])) → text6
  16. If(Element[list1, 1] < 0, (-GCD[Coefficients[final]]), GCD[Coefficients[final]]) → e
  17. Simplify(final(x) / e) → divideoutgcd
  18. Factor(divideoutgcd) → g